Uptake and Metabolism of ¹⁴ C-Labeled Oleic Acid by Atherosclerotic Lesions in Rabbit Aorta

Abstract

The uptake of 14 C-labeled oleic acid and its incorporation into combined lipids by aortic intimas from normal and cholesterol-fed rabbits has been investigated in vitro. More than five times as much oleic acid was taken up by the atherosclerotic intima as by the normal intima. About twice as much oleic acid was incorporated into phospholipid, and twenty times as much into cholesterol ester by the atherosclerotic intima as by the normal. Lecithin was the major phospholipid synthesized from oleic acid in both normal and atherosclerotic intimas.Radioautographs of the atherosclerotic vessels show that the 14 C-labeled oleic acid and its metabolic derivatives, principally phospholipid and cholesterol ester, were localized in sudanophilic cells in the intima in both early and advanced lesions. It is concluded that intimal foam cells are primarily responsible for the lipid synthesis that occurs in the atherosclerotic lesion.ADDITIONAL KEY WORDS fatty acids atheroma foam cells lipid metabolism arterial wall metabolism radioautography phospholipid cholesterol esterFrom the

Effects of Regression of Atherosclerotic Lesions on the Content and Esterification of Cholesterol by Cell-Free Preparations of Pigeon Aorta

“…It has been well established that, in atherosclerotic aortas, the esterification of cholesterol is markedly stimulated (12,13,19). The present study demonstrated for the first time that the regression of atherosclerotic lesions is also associated with a relatively specific decrease in the rate of cholesterol esterification in the lesions themselves.…”

Influence of Duration of Cholesterol Feeding on Esterification of Fatty Acids by Cell-Free Preparation of Pigeon Aorta

“…Results from this study confirm earlier reports of esterification of fatty acids by arterial tissue (21)(22)(23). The present study,and others (4,23) have shown that fatty acids are most readily esterified to phospholipid, but that as arteries become diseased there is a marked shift toward increased esterification of cholesterol.…”

“…The present study,and others (4,23) have shown that fatty acids are most readily esterified to phospholipid, but that as arteries become diseased there is a marked shift toward increased esterification of cholesterol. The increased esterification of cholesterol by atherosclerotic arteries can also be seen with fatty acids synthesized de novo from acetate (4, 5).…”

Discovery of the Role of Wall Shear in Atherosclerosis

“…9,10 They were: (1) realization that the arterial wall can synthesize or modify lipid, apparently from precursors supplied from the lumen, for example, 20,21 ; (2) recognition that wall shear rate could influence the diffusional flux of material between the blood and the arterial wall and would influence to a greater extent the flux of materials with a low than a high diffusion coefficient; (3) recollection of work by colleagues: Schroter and Sudlow 22 had shown in a model study of bronchial airway flow (Figure 1) that near-wall velocity was higher immediately distal to the flow divider at a bifurcation than at the opposite outer wall, leading to the expectation of a similar distribution of near-wall velocity and wall shear at arterial branches. I also recalled having read Fox and Hugh.…”